Neural Signaling
What are the three basic functions of a neuron?
Receive signals, integrate incoming signals, and communicate signals to target cells.
Which lobe is primarily responsible for processing visual information?
The occipital lobe.
Which photoreceptors work best in bright light and detect color?
What is lateralization?
The specialization of certain mental processes primarily in one side, or hemisphere, of the brain.
What snail-shaped structure contains the sensory receptor cells of the auditory system?
The cochlea.
A neuron receives both excitatory and inhibitory signals. What determines whether it will fire an action potential?
The combined/summed effect of the incoming signals; if they reach the required level, the neuron fires.
Which area is associated with speech production, and what happens when it is damaged?
Broca’s area; damage makes it difficult to produce speech.
What structure contains cones and is responsible for the highest-detail vision?
The fovea.
Which side of the brain generally controls the left side of the body?
The right hemisphere.
What are the three bones of the middle ear?
The malleus (hammer), incus (anvil), and stapes (stirrup).
Trace the path of a neural signal from the structure that receives incoming signals to the structure that communicates with the next cell.
Dendrites → soma → axon hillock → axon → axon terminal → synapse.
Which area is involved in language perception and comprehension, and what can happen when it is damaged?
Wernicke’s area; a person can produce speech but has difficulty comprehending language.
What happens to visual information at the optic chiasm?
Information from the two visual fields is separated and sent to the opposite sides of the brain.
What popular idea does research showing no relationship between primarily left-brained and primarily right-brained people challenge?
The left-brain/right-brain personality myth.
What property of a sound wave is associated with pitch, and what property is associated with loudness?
Frequency is associated with pitch, while amplitude is associated with loudness.
What is the function of myelin, and why does its presence make signaling along an axon more efficient?
Myelin insulates the axon and helps nerve impulses travel rapidly and efficiently.
Which lobe contains the motor cortex and prefrontal cortex, and what are their major functions?
The frontal lobe; the motor cortex controls body movements, while the prefrontal cortex is involved in executive functioning.
Someone sees an object in their left visual field. Which side of the brain ultimately processes that information?
The right side of the brain.
Why doesn't the fact that the right hemisphere controls the left side of the body prove that someone is a “right-brained person”?
Contralateral control is a real feature of brain organization, but it does not mean that a person primarily uses one hemisphere or has personality traits determined by that hemisphere.
What is phantom limb pain, and what neurological phenomenon may contribute to it?
It is pain or sensations experienced in an amputated body part; cortical reorganization may contribute by causing surrounding areas of the somatosensory cortex to respond where the missing limb was previously represented.
A neuron receives many signals simultaneously, some excitatory and some inhibitory. At what structure are these signals summed, and what happens if the combined signal reaches the required level?
They are summed at the axon hillock; if the threshold is reached, an action potential is triggered and travels down the axon.
A person has difficulty both feeling touch and determining the spatial arrangement of objects around them. Which lobe is most relevant, and what two functions from your notes are affected?
The parietal lobe; somatosensory processing and spatial perception/manipulation.
A person can see an object but has difficulty identifying what it is, while another person has difficulty determining where it is in space. Which two visual pathways are involved?
The ventral pathway (“what”) is involved in object identification, while the dorsal pathway (“where/how”) is involved in location and interaction with objects.
Researchers found that strongly left- or right-lateralized connections tended to relate to other lateralized connections when they shared a brain region. What does this suggest about how lateralization works?
Brain lateralization involves interconnected networks rather than people simply being globally “left-brained” or “right-brained.”
An amputee experiences sensations from a missing limb. According to your notes, give two possible explanations for how this could happen.
Cortical reorganization can cause surrounding somatosensory areas to respond to the missing limb’s former representation, and the brain may continue to maintain a model of the body and send signals to the missing limb.